Roof with skylight and hollow structural beam elements therefor



Jan. 6, 1970 M. ROOF WITH SKYLIGHT F. SERNA AND HOLLOW 5 ICTURAL BEAM ELEMENTS THEREFO Filed April l2, 1968 4 Sheets-Sheet l Jan. 6, 1970 M. F. SERNA 3,487,596

ROOF WITH SKYLIGHT AND HOLLOW STRUCTURAL BEAM ELEMENTS THEREFOR Filed April 12, 1968 4 Sheets-Sheet z INVENTOR MIGUEL FISAC- SERNA M09 Mew ATTORNEY Jan. 6, 1970 M F. SERNA 3,487,596

ROOF WITH SKYLIGH'I AND HOLLOW STRUCTURAL BEAM ELEMENTS THEREFOR Filed April 12, 1968 4 Sheets-Sheet 5 Jan. 6, 1970 M. F. SERNA 3,437,596

ROOF WITH SKYLIGHT AND HOLLOW STRUCTURAL BEAM ELEMENTS THEREFOR 4 Sheets-Sheet 4 Filed April 12 1968 United States Patent Ofiice 3,487,596 Patented Jan. 6, 1970 US. Cl. 5218 11 Claims ABSTRACT OF THE DISCLOSURE The beam elements, adapted to be stacked end to end with other similar elements form a structural beam; each element, in cross section, is of generally inverted A shape and has a first side portion formed with a first extending fin, a second side portion formed with a second extending fin of lesser length than the first fin, the two side portions being joined at an apex and angled away from each other and a cross-interconnecting section forming junctions with the side portions, reinforcement-receiving holes being formed at the junctions; panel attachments, for example of transparent material, are formed at the ends of the side portions, to interconnect the beams and let light through While forming a waterproof, self-supporting roof beam structure with skylights.

The present application is a continuation-in-part of my earlier filed application Ser. No. 685,606, filed Nov. 24, 1967, and now abandoned.

SUBJECT MATTER OF THE INVENTION A beam structure is formed of several similar, stacked elements which latter elements are hollow, and of substantially triangular section with three stress points in their vertices in which there is situated a post-stressed reinforcement, the location of said stress points being so arranged that the resultant of the forces is situated in the vertical plane of the centre of gravity.

A variant in the form of the section of such elements, without fundamentally altering the characteristics of the invention, permits use in the construction of roofs with spans of 24 metres, while with the triangular elements it was not advisable to exceed a span of 16 metres.

In order to achieve the increase of span, the form of the load-bearing element has been modified with the aim of obtaining a greater bending strength of the said element. This element has proportionately a greater height with respect to the width than the section of the triangular load-bearing element. This section likewise varies in form by adopting a quadrangular instead of a triangular contour with the aim of obtaining a greater section in the lower part than is the case with the triangular form, with the object of obtaining a greater section in the lower stress region.

The said elements likewise incorporate longitudinal fins or visors which are situated above the resulting space between each two adjacent beams and act as screens against the direct sunlight, skylights being formed in the space between beams by means of sheets of transparent or translucent material fixed by their edges in a perfectly hermetic form in channels arranged in the said elements.

The said transparent or translucent sheets, which form the skylight, are of flexible, elastic material and are curved in such a way as to present a convex surface toward the exterior, with the aim of absorbing and adapting themselves to the relative movement or displacement between two consecutive elements.

The elements in question likewise have an appropriate lateral shape so as to make possible the joining of one to another by means of sockets, and likewise for the optimum application of mortar in the said guide joints.

Likewise, the elements and the system of construction are shaped to facilitate the drainage of the roof and the joining of the said roof to the supporting structure.

In order to enable the invention to be better understood, a description is given below of an example of practical construction thereof, in which reference is made to the annexed drawings.

In the said drawings:

FIGURE 1 shows a perspective View of a prefabricated element produced in accordance with the fundamental characteristics of the invention for the formation of resistant and covering elements.

FIGURE 2 shows, in section through a vertical plane, a portion of roofing constructed with the element represented in FIGURE 1.

FIGURE 3 shows, in perspective view, a detail of the lateral end of a roof constructed in accordance with the present invention.

FIGURE 4 shows a longitudinal section of a roof, constructed in accordance with the invention, with beams formed by two pieces, as shown in FIGURE 1, whose section correspond to the plane IVIV of FIGURE 2.

FIGURE 5 shows a detail of the coupling between two end pieces for the formation of the drainage channel and supports of the head pieces to be set in the structure sustaining the complex.

FIGURE 6 shows a detail of a section of a skylight, which emphasizes the curved form of the closure sheet of the said skylight.

FIGURE 7 shows the arrangement of the fundamental axes of the profile of a prefabricated element, with an indication of the situation of its centre of gravity, and the centre of gravity of the three cables which form the reinforcement.

FIGURE 8 shows a section through a vertical plane of a portion of the roof constructed with the elements shown in FIGURE 9.

FIGURE 9 shows a perspective view of a prefabricated element produced in accordance with the fundamental characteristics of the invention and of this present variant.

In the said drawings the numerical references correspond to the following elements and details:

1-Fundamental part of the resistant and covering element.

2-Longitudinal closed hollow element.

3, 4 and 5Ducts for the passage of the post-stressed reinforcement.

6Upper visor.

7-Channel for housing the upper edge of the translucent sheet of the skylight.

8Flange for the fitting of the lower edge of the translucent sheet.

9Channel for the fitting of the lower edge of the translucent sheet.

10Flexible translucent closing sheet of the skylight.

11Projecting piece for the regulation of the concrete in the joints.

12Fin to enable one piece to be fitted to another.

13--M0rtar joining one piece to another.

14-Post-stressed reinforcement.

15Channels or gutters for carrying off rainwater.

16End piece.

17Anchorage for post-stressed elements.

18End covering pieces.

19 and 20Vertical channels for carrying off the water.

21Upper face.

22 and 23Lateral faces.

24-Lower face.

25Transparent flexible sheet for closing the skylight.

26Duct to allow the passage of the post-stressed reinforcement.

27Post-stressed reinforcement.

In accordance with the above-mentioned references, the fundamental prefabricated elements, represented in particular in FIGURE 1, are formed by a hollow piece 1 constructed by means of moulding with suitable material, which said piece includes a longitudinal hollow part 2 of substantially triangular section with a vertex in the lower part, whose lateral partitions are of practically uniform thickness, except in the zone of the vertices where the said partitions present longitudinal orifices or ducts or circular sections 3, 4 and 5, intended to house the cables 14, which will constitute the post-stressed reinforcement. The vertices show a thickness in accordance with the distribution of masses appropriate for the optimum work of the element in its stress resistant and architectural function. The lower part of the piece, in accordance with the normal ararngement of the latter for the formation of a roof, represented in FIGURE 2, is rounded, and joins two substantially plane faces, of which one deviates slightly from the vertical with a forward inclination, and the other, also substantially plane, is inclined to a greater extent. The former of the said faces is prolonged, forming a slight concave curvature in the fin 6, and the second with the fin 8, being shorter than the first.

The fin 6 terminates in a parabolic form and is endowed, in its external lateral face and in its interior zone with a channel 7. The other fin 8 has on its edge another similar channel 9.

FIGURE 7 shows the relationships of the various centers of gravity which arise, and their axes, when the elements are made. The center of gravity A of the profile having the axes X and Y is that of the elements without reinforcement cables. Axes X Y form an angle a with the axes X and Y which correspond to the horizontal and vertical axes of the element with the poststressing cables inserted, that is, as the element would normally be when installed on a roof.

The axis L corresponds to the neutral line when an element is actually placed in position on a roof. It forms an angle b with the horizontal axis X C is the center of gravity of the reinforcing structure alone. It is situated below the neutral line, presenting, with respect to the center of gravity, an eccentricity e. As seen in FIG. 7, center C and center A are on the same vertical axis Y In a preferred structure:

The assembled beams are so placed that between one beam and another a space is formed destined for a skylight, which skylight is closed, by means of the translucent sheet 10 which fit by their edges in the said channels 7 and 9, the said joint being closed by means of a suitable adhesive 13.

As is shown in FIGURE 6, the translucent or transparent sheet 10 has a convex curvature to adjust to possible variation of distance between the two adjacent elements which form the space for the skylight. The said sheet is of an elastic material.

The sheet 10 is provided with an initial curvature such that, when the curvature of the said sheet increases because the relative distance between two adjacent beams reaches the minimum provided for, the said sheet can absorb this greater curvature; when the relative position between two adjacent beams is maximum the sheet is almost taut.

In the said sheets it is always necessary to provide for a length and curvature such as allow the optimum accommodation to the relative displacement of the adjacent beams.

The above-mentioned elements are joined lengthwise to one another, one after the other, until they form beams equivalent to the length of the span to be covered, and consequently the length of each of the elements is a fraction of the said span. In order to facilitate this assembly, the elements are equipped, as is shown in FIGURE 4, with a projecting piece or lug 11 at their ends and a prolongation or overlap in the ends of the hollow 2, which overlap fits into the cavity of the other end, so that the said overlap is found only at one end of each element. Likewise, the anchorage pieces 16 are equipped one with an overlap 12 and the other piece with a corresponding cavity. 7

In order to effect the construction of a roof in accordance with the system which is the subject of the present invention, it sufiices to form, in the first place, the beams by means of prefabricated elements, joining them together one after another in the form indicated. Thereupon the cables 14 are fitted, the end pieces 16 having previously been placed in position, the said pieces having transversal orifices for the fitting of the means of retention 17. The said pieces are formed with a vetrical channel 20 situated in continuation of the concave part 15, which in the pieces 1 is intended for carrying off rain water.

Once the beam has been reinforced with the said end pieces, a cement mortar is introduced into the joints and is allowed to set until it reaches a plastic state, which constitutes the fill 13, and the reinforcement is subjected to stress, in accordance with the known process for poststressing, until it reaches the specified tensional stress.

The beams thus formed are then placed on their supports, situated side by side at pre-established distances so that the said beams are supported by their ends by means of the piece 16 of plane base. Thus, the beams remain in the position shown in FIGURE 2, in which, due to their form, the resultant of the stresses to which the said position is subjected is situated in the vertical plane of the centre of gravity.

The ends are covered with the pieces 18, shown by broken lines in FIGURE 5, serving to form the channel 19 for carrying off the water.

During the positioning of the beams, or subsequent to this operation, the translucent sheets 10 are situated in their channels 7 and 9, and a suitable adhesive is introduced into the said joints in order to provide the necessary degree of watertightness.

FIGURES 8 and 9 show a further embodiment of the invention, but this time the load-bearing element presenting in section a quadrangular form composed by the laterals 22 and 23 converging towards the lower part which is formed by the face 24. The upper face 21 is inclined, and it is prolonged, forming together With the face 22 a visor which is situated above the transparent flexible sheet 25 which serves to close the skylight.

In the Zones of greatest section situated at the angles there are the ducts 26, intended for the housing of the post-stressed reinforcement 27.

These prefabricated elements are constructed in standardized lengths which are joined by coupling one to the other until the length corresponding to the span desired is obtained, thus constituting a load-bearing element poststressed by means of the reinforcements 27.

Various changes of materials, forms and arrangements of the elements may be made without departing from the scope of the invention.

What I claim is:

1. Hollow structural beam element adapted to be stacked, end to end, with other similar elements to form a structural beam, each said element being, in cross section, of generally inverted A-shape, and having a first side portion formed with a first, extending fin;

a second side portion formed with a second extending fin of lesser length than said first fin, said first and second side portions being joined at an apex and then being angled away from each other; and

an interconnecting section forming first and second junctions with said Side portions and interconnecting said side portions at a distance from said apex, said first junction joining said interconnecting section and said first side portion and being located at a distance from said apex different from the distance from the apex of the second junction joining said interconnecting portion with said second portion, the region beneath said interconnecting section and said side sections being hollow;

re-inforcement receiving holes formed in said elements at said apex and said first and second junction;

panel attachment means formed on both said fins adapted to receive panels to interconnect laterally adjacent beam elements;

and interfitting means located at the ends of said elements and matching an adjacent element to fit said elements together in end-to-end stacked relation. 2. Composite structural beam formed of a pluarlity of stacked, aligned and interfitting elements, each according to claim 1, further comprising 7. Roof structure according to claim 5 wherein said panel attachment means formed on said first side portion is a groove located intermediate said extending fin and at the underside therof, and said panel attatchment means formed on said second side portion is a groove formed at the terminal end of the second extending fin, said panels being set into and sealed in said grooves;

and the fin on said first sid portion is formed to arch over and at least partialy overlap said panel.

8. Composite structural beam according to claim 2 wherein the upper part of said interconnecting section and said second side portion are joined together at a rounded, converging rain trough.

9. Composite structural beam according to claim 2 wherein said infitting means comprises extending portions formed at one end of each element and projecting beneath at least part of the hollow space defined by said side portions and said interconnecting sections.

10. Hollow beam element according to claim 1 Wheremeans sealing said elements together in the region of in the apex joining said side portions together is flattened;

said interfitting ends;

post-stressed re-inforcement means passing through said re-inforcing receiving holes; and

means connected to said re-inforcing means anchoring and more than one re-inforcement hole is located at said apex.

11. Composite structural beam formed of a plurality of stacked, aligned and interfitting elements, each in acsaid re-inforcing means at the terminal ends of the cordance with claim 10, wherein at least two holes are first and last of said elements. 3. Composite structural beam according to claim 2 wherein said re-inforcing holes and thus re-inforcing means are located in said elements symmetrically with respect to the center of gravity of said beam elements.

4. Composite structural beam according to claim 2, wherein said elements have a first center of gravity located at horizontal and vertical axes; said post stressing reinforcement means have a second center of gravity; and

said second center of gravity is located on said vertical axis.

5. Roof structure formed of an assembly of structural beams, placed laterally side by side, each beam in accordance with claim 2, including panels secured to and sealed to said panel attachment means and interconnecting ad- 4( formed in said apex, a separate post-stressed re-inforce ment means is provided and located in each said holes, and means are provided and connected to said re-inforcement means anchoring said re-inforcement means at the terminal ends of the first and last of said elements whereby additional tensile strength is provided at the lower side of the composite beam.

I References Cited UNITED STATES PATENTS 484,263 10/ 1892, Tinnemeyer 52227 X 2,238,311 4/1941 Dyer 52606 2,705,929 4/1955 Atkins 5218 FOREIGN PATENTS 619,198 3/1961 Italy.

419,534 3/1967 Switzerland.

FRANK L. ABBOTT, Primary Examiner P. C. FAW, JR., Assistant Examiner U.S. CL. X.R. 

